<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			.box{
				width: 400px;
				height: 400px;
				background: red;
			}
		</style>
		<script src="js/jquery.min.js" type="text/javascript" charset="utf-8"></script>
		<script type="text/javascript">
			
			$(function(){
				$('#btn').click(function(){
//					获取css样式
					var a = $('.box').css('background-color')
//					设置一种css样式
					 $('.box').css('background-color','blue')
//					 设置多个css样式
					 $('.box').css({'background':'yellow','border':'5px solid green'})
					console.log(a)
				})
			})
		</script>
	</head>
	<body>
		<input type="button" id="btn" value="点击" />
		<div class="box">
			
		</div>
	</body>
</html>
